This invention relates generally to lighting systems for swimming pools and, more particularly, to fiber optic cable assemblies that are mounted along the perimeter of above-ground swimming pools.
Submersible electric lights for the illumination of swimming pools and spas have become well known over the years. More recently, it has become popular to use fiber optic cables in swimming pool lighting systems. Fiber optic systems consist basically of a remote light source and either or a combination of two types of fiber optic cable namely end light or side light cable. End light fiber optic cable is designed to emit light from the end of a fiber opposite the light source to either provide a directly viewed point of light or to cast illumination upon an area. Side light fiber optic cable, with a clear or translucent jacket, takes advantage of light escaping from the side of the fiber or bundled fibers to deliver an effect similar to neon light for direct viewing.
One example of side light fiber optic perimeter lighting may be found in U.S. Pat. No. 5,680,496. That patent sets forth a perimeter lighting assembly which is mounted in a track around the pool periphery. The fiber optic cable assembly includes a bundle of fiber optic fibers, a tube, a track, a plurality of fasteners and securing means. The tube has a front surface and a rear surface and the bundle of fiber optic fibers is contained within the tube. The tube has flanges which fit within the track and fasteners are employed to secure the track to the side of the pool.
This arrangement is suitable for in-ground pool lighting but does not adapt well to above-ground installations because of the expense of a system effective in delivering adequate under water (end-out) and perimeter (side-out) illumination. Part of this expense is due to the cost of the fiber optic cable between its remote light source and the pool wall. Because there is a natural loss of light over distance in fiber optic cable, the fiber optic cable required between a remote light source and the pool also reduces the amount of light transmitted, reducing the light efficiency of the system. Another part of this expense is due to the large fiber cable or powerful remote light surface required to provide adequate under water illumination. Dark surfaces are more difficult to effectively illuminate than lightly colored surfaces and only very expensive fiber optic systems deliver acceptable or adequate under water illumination of darker surfaces. The vast majority of above ground pools have dark liners or liners with dense, dark, printed patterns.
Copending application Ser. No. 09/193,331 provides a perimeter lighting system which delivers adequate under water illumination and economical perimeter (side-out) fiber optic illumination by using a submersible incandescent light fixture for direct under water illumination as well as for the light source for the fiber optic cable for perimeter and other fiber optic features in the pool environment.
That application also provides adequate direct under water illumination while at the same time provides a light source for fiber optic fibers and/or fiber optic cable is for functional and/or aesthetic illumination in the pool environment.
According to that application, a fiber optic pool perimeter lighting system is provided for an above-ground pool having a pool wall and a top perimeter mounted on the pool wall. The system comprises an above-ground pool light fixture mounted in the pool wall below the water level. The light fixture is preferably of the type set forth in U.S. Pat. No. 5,207,499 and includes an outer shroud having an inlet passage for inlet pool water. A concentric water proof tube is mounted within the shroud to house the electrical connections and a light fixture. The light fixture is covered by a lens and the shroud terminates in an annular grid which serves to admit water to the pool. A light adapter cup is mounted between the light fixture lens and the grid so that the cup locates fiber ends in the optimum or near optimum light focus spot of the light fixture. The cup has a side wall and an end wall and a flexible fiber optic cable bundle has an end mounted in an opening in the end wall so that the fiber optic cable bundle end is in substantial axial alignment with the light source. A rail adapter is mounted on the top perimeter of the pool. The rail adapter is a U-shaped channel having a base portion and a pair of parallel legs extending upwardly to engage a downwardly extending flange lip of the top perimeter. The rail adapter is fixed to the flange lip by driving wedges between the lip and a leg of the U-shaped channel and silicone is injected through ports in the channel to firmly retain the rail adapter on the flange lip. A hollow flexible tube case is connected at one end to the opening in the cap and is connected at its other end to the base portion of the rail adapter. The flexible fiber optic cable bundle has a first and a second branch leg extending as a unit from the opening in the end wall of the cap, through the tube case, into the U-shaped channel, and branching individually along the flange lip in opposite directions. Any excess cable may be retained by a similar U-shaped channel.
The fiber optic cable bundle according to that application includes a flat flexible ribbon having an integral tube formed along one edge of the ribbon and a multiplicity of individual fiber optic fibers longitudinally extending in the tube. This arrangement provides a flat flexible tail which allows the cable to be fixed to the perimeter rail by an adhesive to the rearward side of the downwardly extending flange lip on the top perimeter rail. The tail may also be stapled to wooden deck structures. By allowing the cable tail and adhesive to be out of view, the adhesive does not have to have a smooth clear finish. This results in simpler installation by an untrained consumer.
The flexibility of the tail allows the tail to conform to the many diverse shapes of the underside of an above ground pool ledge. This flexibility also allows for conforming to and around irregularities in above-ground pool rail connections and corners on spa cabinets without kinking the fiber optic cable. Such kinking would cause undesirable bright spots and inhibit further light transmission in the fibers. Since the cable according to that application is designed with a loose fitting jacket or tube surrounding the multiple small polymethyl methacrylate fibers, the cable is able to conform to the above mentioned surface irregularities without creating bright spots or hindering continued light transmission. The fiber accommodates a 0.24 inch bend radius and the cable allows a 0.5 inch bend radius without kinking.
While the fiber optic cable and rail adapter assembly according to the copending application solves a number of problems relating to light transmission and cable mounting in above-ground pools, it is desirable to provide an assembly that may be installed on a wider variety of top rails and which eliminates the need for adhesives in some applications. Even though adhesives may be applied by unskilled personnel, it is a time consuming job that requires some degree of care. Further, prior to installation the pool should be partly drained until the water level is just above the bottom of the skimmer port and the front side of the fiber optic cable and the backside of the top rail inner wall should be cleaned with isopropyl alcohol and dried thoroughly. After installation, the cable adhesive should be permitted to cure for at least 24 hours prior to use.